Hollywood's widening sexual harassment crisis has ensnared a prominent film director after six women — including actress Olivia Munn — accused Brett Ratner of sexual assault or misconduct in a Los Angeles Times report today.

Munn also complained about onset behaviour, alleging that while visiting the set of Ratner's After the Sunset in 2004, he masturbated in front of her in his trailer. Munn described the incident, without naming Ratner, in a 2010 collection of essays.

A year later, Ratner himself identified himself as the director mentioned by Munn, boasting he had “banged” her – a claim Munn has since disputed.

“I've made specific, conscientious choices not to work with Brett Ratner,” Munn said.

“It feels as if I keep going up against the same bully at school who just won't quit.

“You just hope that enough people believe the truth and for enough time to pass so that you can't be connected to him anymore.”

Actress Natasha Henstridge also accused Ratner of “physically forcing” her to perform oral sex on him when she was a 19-year-old fashion model. Henstridge later stared in Species and The Whole Nine Yards.

Ratner's lawyer issued a statement in which he said the director "vehemently denies the outrageous derogatory allegations" and is "confident that his name will be cleared once the current media frenzy dies down and people can objectively evaluate the nature of these claims".

“I have represented Mr. Ratner for two decades, and no woman has ever made a claim against him for sexual misconduct or sexual harassment,” he said in a letter to The Times.

“Furthermore, no woman has ever requested or received any financial settlement from my client.”

Ratner directed the Rush Hour film series, Red Dragon, X-Men: The Last Stand and Tower Heist.

In 2011, he resigned from producing the 2012 Academy Awards after joking “rehearsal is for fags” at a screening for Tower Heist.

US actress Katherine Towne. (IMDB)

Warner Bros, which has a first-look deal with Ratner, said in a statement: "We are aware of the allegations in the LA Times and are reviewing the situation".

Ratner together with 80-year-old actor Dustin Hoffman become the latest Hollywood figures to face allegations of misusing their power to harass actresses, a list that now includes producer Harvey Weinstein and writer-director James Toback.

Harassment allegations have also been levied against actors Kevin Spacey and Jeremy Piven.